# A019220 (b-file synthesized from sequence entry) 3 1 4 1 5 0 6 2 7 0 8 10 9 20 10 100 11 206 12 528 13 1008 14 2594 15 5618 16 15246 17 37564 18 100604 19 249758 20 651804 21 1633514 22 4233788 23 10771236 24 28036370 25 72289144 26 188906208 27 490896946 28 1286263486 29 3361239986 30 8831282324 31 23185222496